The present invention relates to a spectacle lens machining method and apparatus which form holes, notches, and grooves or the like used for the attachment of parts to the outer circumferential end surfaces or the like of a spectacle lens.
In recent years, rimless type spectacles (rimless spectacles) have attracted attention because of the advantages offered by such spectacles in terms of a broad field of vision, light weight and the like. Such rimless type spectacles include a type in which the circumference of the lower part of each lens is supported by a nylon thread, known as the xe2x80x9cNylorxe2x80x9d type, a type called the xe2x80x9ctwo-pointxe2x80x9d or xe2x80x9cthree-piecexe2x80x9d type in which screw holes are formed through the lenses, and the lenses are fastened in place by screws that are passed through these screw holes, and the so-called xe2x80x9cPINFEELxe2x80x9d type, in which blind holes are formed in the edge surfaces of the lenses, and pin-form projecting parts of the spectacle lens holding members are inserted and fastened in these blind holes. Rimless spectacles of the various types described above have respective special features. However, in the case of such spectacles, it is not always easy to achieve a design that sufficiently ensures a wide effective field of vision, durability, esthetic appearance and a reduction in weight, etc., for lenses of various thicknesses and various materials. Furthermore, such spectacles are not always satisfactory from the standpoint of machining costs and the like.
In recent years, therefore, rimless spectacles of a type in which cutouts or the like are formed in the edges of the spectacle lenses, and attachment members are attached by being inserted into these cutouts, have been proposed. For example known spectacles of this type include the spectacles described in Japanese Patent No. 2997438 (Japanese Patent Application Laid-Open No. H10-228000), the spectacles described in Japanese Utility Model Registration No. 2602605 (Japanese Utility Model Application Laid-Open No. H7-32620, and the spectacles described in Japanese Patent Application Laid-Open No. 2000-147435.
In the case of spectacle lenses, the magnification ordinarily varies from user to user, and the shape of the lenses also depends on the shape of the frames selected by the user. Accordingly, the thickness and shape of spectacle lenses generally show individual variations. Consequently, when lenses used in the rimless spectacles involved in the abovementioned proposals are machined by a machining apparatus with numerical control or the like, it is necessary to perform complicated positioning machine on a case by case basis in accordance with the shape and thickness of the lenses, so that the machining efficiency is conspicuously poor.
With the foregoing in view, it is an object of the present invention to provide an spectacle lens machining method and apparatus which make it possible to perform machining that forms holes or notches or grooves or the like for the attachment of parts to the outer circumferential edge surfaces of lenses of various lens patterns, both accurately and with good reproducibility, by means of a simple operation.
The first means used as means for solving the abovementioned problems constitute a spectacle lens machining method for machining spectacle lenses using a machining apparatus after spectacle lens edging has been performed in which the abovementioned spectacle lenses are edged so that they conform to the spectacle frame shape, wherein the machining by the abovementioned machining apparatus is performed with the spectacle lenses fastened to spectacle lens fastening devices which are disposed in the vicinity of the machining position of the abovementioned machining apparatus, the abovementioned spectacle lens fastening devices being equipped with fastening parts that fasten the abovementioned spectacle lenses in a specified positional relationship, and the abovementioned spectacle lens fastening devices positioning the abovementioned spectacle lenses fastened to the abovementioned fastening parts by adjusting the positions of the abovementioned spectacle lenses relative to the abovementioned machining apparatus, and, as the fastening devices, are used those device said fastening parts of which have a structure in which the spectacle lenses are fastened to the fastening devices by fastening spectacle lens holding jigs which are attached to the machining reference positions of the spectacle lenses beforehand as jigs for fastening the spectacle lenses to the edging machine during the abovementioned edging.
The second means comprise a spectacle lens machining method in which a spectacle lens of a specified shape is machined by means of a machining apparatus, this method comprising a spectacle lens holding jig attachment step of attaching a spectacle lens holding jig to a specified position on the abovementioned spectacle lens, a spectacle lens fastening step of fastening the abovementioned spectacle lens by mounting the abovementioned spectacle lens holding jig in a spectacle lens fastening device which is disposed in the vicinity of the machining position of the abovementioned machining apparatus, which fastens the abovementioned spectacle lens in a specified positional relationship as a result of the mounting of the abovementioned spectacle lens holding jig, and which positions the abovementioned spectacle lens by adjusting the position of the abovementioned spectacle lens fastening device, a positioning step of positioning the spectacle lens by adjusting the position of the abovementioned spectacle lens fastening device so that a specified position on the abovementioned spectacle lens is caused to contact a specified position on a positioning reference plate which is disposed in the vicinity of the abovementioned machining apparatus and which is constructed so that when a specified position on the abovementioned spectacle lens is caused to contact the abovementioned specified position on this positioning reference plate, the machining area of the abovementioned spectacle lens is maintained in a fixed positional relationship with a machining reference position of the machining apparatus, and a machining step of machining the spectacle lens (which has been positioned by the abovementioned positioning step) by means of the abovementioned machining apparatus.
The third means comprise the spectacle lens machining method of the second means, wherein a spectacle lens holding jig which is attached to the machining reference position on the spectacle lens beforehand as a jig which is used to fasten the spectacle lens to a lens edging machine prior to the edging of the spectacle lens in which the spectacle lens is edged so that the abovementioned spectacle lens conforms to the frame shape is used as the abovementioned spectacle lens holding jig, and the abovementioned spectacle lens holding jig attachment step is performed prior to the abovementioned spectacle lens edging.
The fourth means constitute the spectacle lens machining method of any of the first through third means, wherein the abovementioned machining apparatus that machines the spectacle lenses after said edging has been performed is a cutting machining apparatus which is controlled by numerical control.
The fifth means constitute a spectacle lens machining apparatus for machining spectacle lenses after spectacle lens edging has been performed in which the abovementioned spectacle lenses are edged so that they conform to the spectacle frame shape, wherein the abovementioned spectacle lens machining apparatus has spectacle lens fastening devices which are disposed in the vicinity of the machining position of the abovementioned machining apparatus, the abovementioned spectacle lens fastening devices being equipped with fastening parts that fasten the abovementioned spectacle lenses in a specified positional relationship, and the abovementioned spectacle lens fastening devices positioning the abovementioned spectacle lenses fastened to the abovementioned fastening parts by adjusting the positions of the abovementioned spectacle lenses relative to the abovementioned machining apparatus, and the abovementioned fastening parts have a structure in which the spectacle lenses are fastened to the fastening devices by fastening spectacle lens holding jigs which are attached to the machining reference positions of the spectacle lenses beforehand as jigs for fastening the spectacle lenses to the edging machine during the abovementioned edging.
The sixth means constitute a spectacle lens machining apparatus comprising a machining apparatus which machines spectacle lenses, spectacle lens fastening devices which are disposed in the vicinity of the machining position of the abovementioned machining apparatus, these spectacle lens fastening devices having fastening parts which fasten, in a specified positional relationship, spectacle lens holding jigs that are attached to the machining reference positions of the spectacle lenses beforehand as jigs for fastening the spectacle lenses to the edging machine during the abovementioned edging, said spectacle lens fastening devices further fastening the abovementioned spectacle lenses in place by fastening the abovementioned spectacle lens holding jigs to the abovementioned fastening parts, and said spectacle lens fastening devices further having position adjustment mechanism parts which position the abovementioned fastened spectacle lenses by adjusting the positions of these lenses relative to the abovementioned machining apparatus, and a positioning reference plate which is disposed in the vicinity of the machining position of the abovementioned machining apparatus, this positioning reference plate having positioning contact parts which are constructed so that the machined parts of the abovementioned spectacle lenses are in a fixed positional relationship with the machining reference position of the abovementioned machining apparatus when specified positions on the abovementioned spectacle lenses are caused to contact specified positions on the abovementioned positioning reference plate, wherein positioning of the abovementioned spectacle lenses is accomplished by adjusting the positions of the abovementioned spectacle lenses by means of the abovementioned spectacle lens fastening devices so that specified positions on the abovementioned spectacle lenses are caused to contact specified positions on the positioning contact parts of the abovementioned positioning reference plate, and the abovementioned spectacle lenses are machined by the abovementioned machining apparatus.
In the abovementioned first and fifth means, the spectacle lens holding jigs that are attached to the machining reference positions of the spectacle lenses beforehand as jigs for fastening the spectacle lenses to the edging machine during edging can be utilized xe2x80x9cas isxe2x80x9d and fastened to the fastening devices; accordingly, the operation of fastening the spectacle lenses to the fastening devices can be performed simply and accurately.
In the abovementioned second, third, and sixth means, a spectacle lens holding jig is attached to a specified position on the spectacle lens, this holding jig is fastened to a fastening device, and a specified position on the spectacle lens is caused to contact a specified position on a positioning reference plate. As a result, the spectacle lens can be positioned so that the machining area of the spectacle lens is in a fixed positional relationship with the machining reference position of the abovementioned machining apparatus. Consequently, the machining area of the lens can be quickly and easily fastened in the machining position even if the thickness and shape of the lens vary.
In the abovementioned fourth means, cutting machining using numerical control can be efficiently performed.